Rhodomonas salina是一种Cryptophyta（隐藻门）中的Rhodomonas属，是水产养殖和产生光合色素红藻素（PE）的有价值的活性饲料。本研究从Rhodomonas salina中提取红藻素，并表征其分子量约为24kDa，吸收波长为545nm，纯度高达6.61（其OD545/OD280比值大于4符合试剂级要求）。 评估红藻素对抗癌活性及其潜在机制，以评估其对人类肺癌A549细胞株的免疫调节潜力。应用生化分析和西方印迹分析以确认免疫机制。结果表明，暴露于红藻素24h后，A549细胞的增殖显著地、剂量依赖性地降低。红藻素还会导致反应性氧化物（ROS）的生成和线粒体膜电位（MMP）的降低。进一步的结果表明，红藻素可以显著增强cleaved caspase-3和p53蛋白水平。同时，BCL-2家族也受到影响，并发生了一些变化，如Bim和Bak的显著增强以及Bcl-2水平的降低。然而，值得注意的是，在实验过程中，Bax表达似乎没有明显变化。此外，潜在的PE诱导凋亡的生物学机制表明，ERK/Bak和JNK/caspase-3信号通路被激活。本研究提供了Rhodomonas salina中PE的抗癌活性可能具有预防癌症和作为制药行业中新型免疫刺激剂的潜力的证据。Copyright © 2023. Elsevier B.V.发表。

Rhodomonas salina, Cryptophyta, Rhodomonas genus, is a valuable source for live feed in aquaculture and for the production of phycoerythrin (PE). In this study, PE was extracted from Rhodomonas salina and characterized as having a molecular weight of approximately 24 kDa, an absorbance at 545 nm, and a purity of up to 6.61 (which meets reagent grade requirements with an OD545/OD280 ratio >4). The effects of PE on anticancer activity and its underlying mechanisms were evaluated to assess the immunomodulatory potential on the human lung cancer A549 cell line. Biochemical assays and western blot analysis were applied to confirm the immune mechanisms. The results showed that after 24 h of exposure to PE, the proliferation of A549 cells was significantly and dose-dependently decreased. PE also caused the generation of reactive oxygen species (ROS) and a decrease in mitochondrial membrane potential (MMP). The further results showed that PE can remarkably enhance the protein levels of cleaved caspase-3 and p53. Simultaneously, the BCL-2 family was also affected and had some changes, such as the dramatically enhance of Bim and Bak and the decrease of Bcl-2 level. However, it is interesting to note that there was no apparent alteration in Bax expression during the experiment. Furthermore, the biological mechanism for the potential of PE to induce apoptosis showed that the ERK/Bak and the JNK/caspase-3 signaling pathway were activated. This study provides evidence that the anticancer activity of PE in Rhodomonas salina may have potential for preventing cancer and serving as a novel immunostimulant in the pharmaceutical industry.Copyright © 2023. Published by Elsevier B.V.